Poster 144 - Inhibition of coagulant, phospholipasic, fibrinogenolytic and miotoxicity activities

Poster 144. Congresso da Sociedade Brasileira de Toxinologia, 8., Symposium of the Pan American Section of the International Society on Toxinology, 8., 2004, Angra dos Reis, Brasil. Abstracts... J. Venom. Anim. Toxins incl.Trop. Dis., 2004, 10, 3, p.503.

Inhibition of Coagulant, Phospholipasic, Fibrinogenolytic and Miotoxicity Activities Induced by Bothrops neuwiedi Venom by Extract of Schizolobium parahyba.

Mendes, M. M; Izidoro, L. F. M; Coelho, R. B; Hamaguchi, A; Homsi-Brandeburgo, M. I; Rodrigues, V. M.

Instituto de Genética e Bioquímica; Universidade Federal de Uberlândia, Minas Gerais, Brasil.

This study reported the ability of the aqueous extract from leaves of Schizolobium parahyba to neutralize the venom of Bothrops neuwiedi in the coagulant, phospholipase A2, fibrinogenolytic and miotoxicity by determination of plasmatic creatina kinase. The aqueous extract (EV) was prepared by mixing the leaves (300g) with destiled water (150ml) and centrifuged at low rotation for 10 minutes, 4°C, supernatante was liophilized and stored. The coagulant activity on bovine plasma was carried out at 37°C, using 10mg of venom (VB)(positive control) and 500mg of EV (negative control) and test groups: VB and EV were incubates for 15 minutes, VB and EV without incubation. The phospholipase A2 activity was determined by potenciometric titration effected on egg yolk a substract. The fibrinogenolytic activity was evaluated by SDS-PAGE with 50mg of fibrinogen and 10mg of VB. This three test were realized in the ratios 1:20 and 1:50 (m/m). The myotoxicity induced by venom was determined by plasmatic creatine kinase activity. Groups of Swiss male mice(n=4) were injected i.m. in the right gastrocnemius with doses of 25mg of VB. Were used three conditions: preincubation of VB with the EV for 15 minutes; before envenomatiom treatment with the extract; treatment with extract for 15 minutes after envenomation (in the ratio 1:10 m/m) and control PBS.Three hours after injection the animals were killed. Applying Kruskal-Wallis statistic test was noticed that coagulant activity was inhibited by increasing the time of coagulation in three times in the ratio 1:50 with incubation by 15 minutes. The PLA2 was inhibited 63.5%. The fibrinogenolytic activity EV protect chains a and b in the ratio 1:20. For the myotoxicity the best result was preincubation with 30% of inhibition. The extract was effective to inhibit the activities tested. Our results clearly indicates that the aqueous extract of leaves from Schizolobium parahyba contains compounds capable to neutralize the harmful effects induced by Bothrops venoms.